Device for driving a working member of rotary type in a mechanized drifting shield



NOV. 11, 1969 1 ET AL 3,477,301

DEVICE FOR DRIVING A WORKING MEMBER OF ROTARY TYPE .IN A MECHANIZEDDRIFTING SHIELD Filed March 1., 1967 INVENTORS.

EVEENY H. BOLOT/N 21' m.

1J2, /z mw' 914M;

ATTOWIEYS v United States Patent 4 3,477,301 DEVICE FOR DRIVING AWORKING MEMBER OF ROTARY TYPE IN A MECHANIZED DRIFTING SHIELD EvgenyMoiseevich Bolotin, Otkrytoe shosse 24, korp. 25, kv. 12;- LevAbramovich Blyakher, Poledny per.

'1/ 22, kv. 6; Boris Nikolaevich Ierusalimsky, Otkrytoe shosse 24, korp.A, kv. 45; Leonid Ivanovich Saveliev, Otkrytoe shosse 29, korp. 11, kv.58; Vladimir Ivanovich Razmerov, Leningradsky prospekt 62, kv. 90;Leonid Konstantinovich Khaidurov, Otkrytoe shosse 24, korp. 5-g, kv 31,all of Moscow, U.S.S.R.

Filed Mar. 1, 1967, Ser. No. 619,798 Int. Cl. F16h 27/02, 31/00 US. Cl.74--129 2 Claims ABSTRACT OF THE DISCLOSURE The present inventionrelates to devices used in mechanized drifting shieldsfor driving rotarytype working members.

The working member of known drifting shields is imparted a rotary motionfrom an electric motor or a plurality of hydraulic motors through areducing gear meshing with a toothed or pin wheel connected to saidworking member. It is known that the efficient mining of ground requiresa substantial torque at the shaft of the working member which involvesthe application of high power motors.

These motors in conjunction with reducing gears have large dimensions.Therefore it is difficult to dispose them inside a drifting shieldespecially those employed for mining granular grounds, such as sand orsandy loam where it is necessary to apply high torques with low speedsof rotation of the working member.

The present invention provides for an improved construtcion of a deviceof small dimensions for driving the working member, permitting theobtention of substantial torque on the shaft of the working member.

According to the ,present invention, this is achieved by employing atleast two pairs of double-action hydraulic cylinders and tworatchet-and-pawl mechanisms whose working or ratchet wheels are fixed onthe shaft of the working member, each moving element of said mechanismscomprising pawls being pivotally attached to a pair' of said cylinderswhich create a couple of forces transmitted through saidratchet-and-pawl mechanisms to the shaft of the working member. In orderto obtain a con tinuous rotation of the working member, the pawls ofeach mechanism are displaced relative to each other in the direction ofrotation of the ratchet wheels, for example, by a value of a tooth ofthe ratchet wheel, whereas each of said cylinders is provided with anadditional hole in the middle part thereof for letting out the workingliquid in order to create a dilference of stroke speeds for said pairsof cylinders.

For reversing the working member of the device, it is provided withremovable inserts put into tooth spaces of the ratchet wheels.

The present invention may be made more fully apparent from aconsideration of the following description 'ice of an exemplaryembodiment, taken in conjunction with the appended drawings, in which:

FIG. 1 is a fragmentary side view of the mechanized drifting shieldcomplete with a device for rotating the working member;

FIG. 2 is a section on the line A-A of FIG. 1;

FIG. 3 represents a scaled up fragmentary view of the working or ratchetwheel complete with a removable insert set into a tooth space thereofand designed for reversing the working member.

. Therotary device 4 for rotating the working member 3 andtwo-ratchet-and-pawl mechanism 5 and 5 (FIGS. 1 and 2) whose ratchetwheels 6 and 6' are rigidly secured on the shaft 7 of said workingmember 3. Loosely mounted on each wheel 6 and 6' are two checks 8 withpawls 9 and 9 pivotally attached thereto, that are essentially movingvelements of said ratchet-and-pawl mechanisms 5 and 5'. The pawls 9 and9' are pressed to the ratchet wheels 6 and 6' by springs, 10, said pawls9 and 9' of separate ratchet-and-pawl mechanisms 5 and 5 being displacedrelative to each other in the direction of rotation of the ratchetwheels 6 and 6 (shown with an arrow in FIG. 2), for example, within atooth of the ratchet wheel.

Pivotally attached to the cheeks 8 of each ratchet-andpawl mechanism 5and 5' with theirmoving elements 11 and 11' are two pairs ofdouble-action cylinders 12 and 12' operated turning andcreating a coupleof forces. The availability of at least two pairs of hydraulic cylinders12 and 12' is accounted for by the necessity of ensuring the continuousrotation of the working member 3.

Each hydraulic cylinder of said pairs of cylinders 12 and 12', apartfrom the holes 13 and 14 for eifecting idle and working strokes, has anadditional hole 15 disposed in the middle part thereof (FIGS. 1 and 2)for letting out the working liquid passed, for example, through athrottle (not shown in FIG. 2). Thanks to the presence of the additionalhole 15, it is possible to obtain a difference of stroke speeds for saidtwo pairs of cylinders 12 and 12' complete with moving elements 11 and11', which ensures the interception of a tooth by the pawls 9 and 9 ofthe ratchet-and-pawl mechanisms 5 and 5'. This is accomplished in thefollowing manner.

At a time when one of the two pairs of cylinders 12 and 12' terminatesits working stroke, another pair disengages and begins an idle stroke.During the operation of the first pair of cylinders, say the pair ofcylinders 12, the second pair of cylinders 12', having completed an idlestroke, comes into its initial position for the beginning of motion andrests therein unmovable until the tooth spaces of the ratchet wheel 6'arrive in conjunction therewith and the pawls 9 of the ratchet-and-pawlmechanism 5 engage them. Then the second idle pair of cylinders 12starts the forward stroke. In such a way both pairs of cylinders 12 and12' operate together for some period of time.

At that time the pistons of the first operating pair of cylinders 12pass the additional holes 15 through which a portion of the workingliquid is removed resulting in a deceleration of the stroke speed of themoving elements 11 of the pair of cylinders 12 and providing thereby thedifference of stroke speeds for both pairs of cylinders 12 and 12.

The pawls 9' of the ratchet-and-pawl mechanism 5 catch up with the teethof their ratchet-wheel 6, and for a certain period of time the secondpair of cylinders 12' operates together with the first pair of cylinders12 imparting the rotation to the shaft 7 of the working member 3 throughthe ratchet-and-pawl mechanism 5 and 5'. From then on the first pair ofcylinders 12 is switched over for an idle stroke, and the pawls 9disengage teeth of the ratchet wheel 6, whereas the second pair ofcylinders 12 makes the working stroke, thus continuing to rotate theshaft 7 of the working member 3. The cycle is repeated thereuponresulting in the continuous rotation of the working member 3.

The proposed gearing diagram of rotation of the working member 3 permitsthe interception of teeth of the ratchet wheels 6 and 6' through anacceleration at the beginning of the motion of one pair of cylindersrelative to another pair of cylinders whose speed at the given momentremains constant.

The operation of the pairs of cylinders 12 and 12' is controlled througha slide-valve switchgear 16 (FIG. 1) actuated by means of shaped earns17, for example, mounted on the shaft 7 of the working member 3.

Reversal of the working member 3 is accomplished by the aid of removableinserts 18, for example (FIG. 3), put into tooth spaces of one or tworatchet wheels 6 and 6' and secured to cheeks 8 of the ratchet-and-pawlmechanisms. In this case, the moving elements 11 and 11' of the pairs ofcylinders 12 and 12 should be placed into the extreme exposed positionthereof, and the rotation of the working member 3 be accomplished due tothe reversing stroke of the cylinder 12 and 12'. The working member 3may be also reversed by the aid of additional pawls (not shown) arrangedbetween the cheeks 8 and directed backwards with respect to the pawls 9and 9'.

In conformity with the present invention, the above describedconstruction ensures the reliable operation of the working member ingrounds ranging from those of a medium hardness to granulated ones,providing thereby sufiicient torque at preset speeds of rotation of theworking member.

What is claimed is:

1. In a mechanized drifting shield, a device for rotating the workingelement of a rotary type, which comprises: a shaft on which said workingelement is secured, two

ratchet-and-pawl mechanisms, each of which is provided with a workingwheel rigidly secured on the shaft of said working element, and amovable part interacting with said working wheel, ratchet pawls of saidratchet mechanisms taken individually pivotally attached to the movingparts of said mechanisms, the ratchet pawls of one ratchet mechanismbeing mutually displaced relative to the pawls of the other mechanism inthe rotation direction of said working wheels, at least two pairs ofdouble action hydraulic cylinders, the moving elements of each beingjointly connected with said movable part of said ratchetand-pawlmechanisms in such a way, that in their forward motion they create acouple, said hydraulic cylinders being provided with holes for deliveryand draining of working fluid, and an additional hole in the middle partfor letting out the working fluid in order to create a difference ofstroke speeds for the said pairs of the cylinders to ensure thecontinuous rotation of the working element.

2. A device for driving a rotary-type working member as claimed in claim1, which is provided with removable inserts secured on the movableportions of said ratchetand-pawl mechanisms and entering the recesses ofthe working wheels thereof to reverse the working member.

References Cited UNITED STATES PATENTS 2,760,766 8/1956 Mayo 299312,797,795 7/ 1957 West. 2,947,187 8/1960 Graif et a1 74l29 X MILTONKAUFMAN, Primary Examiner.

US. Cl. X.R. 299-33

